Breathe Strong Perform Bettter - Anatomy and physiology of muscles involved in breathing Anatomy and physiology of muscles involved in breathing This is an excerpt from Breathe Strong, Perform Better by Alison McConnell. Breathing Pump Muscles The breathing pump muscles are a complex arrangement that form a semirigid bellows around the lungs. Essentially, all muscles that attach to the rib cage have the potential to generate a breathing action, but the principal muscles are shown in figure 1.7. Muscles that expand the thoracic cavity are inspiratory muscles and induce inhalation, while those that compress the thoracic cavity are expiratory and induce exhalation. These muscles possess exactly the same basic structure as all other skeletal muscles, and they work in concert to expand or compress the thoracic cavity. Inspiratory Muscles The principal muscle of inspiration is the diaphragm, a domed sheet of muscle that separates the thoracic and abdominal cavities. The diaphragm attaches to the lower ribs, as well as to the lumbar vertebrae of the spine. When the diaphragm contracts, the dome flattens, moving downward into the abdominal cavity like a piston (think of a syringe barrel).

This movement increases the volume of the thoracic cavity, creating a negative pressure that is proportional to the extent of its movement, and thus, to the force of contraction. Diaphragm contraction also induces the lower ribs to move upward and forward, which also increases thoracic volume. The ribs move outward because the central tendon of the diaphragm (at the crown of the dome) pushes down onto the liver and stomach, which act like a fulcrum. This has the effect of raising the edges of the diaphragm, which are connected to the rib margins, forcing them upward and outward. When the diaphragm moves downward into the abdominal compartment, it also raises intraabdominal pressure and assists the abdominal muscles in stabilizing the spine. The muscles of the rib cage are known as the intercostal muscles because they are located in the space between adjacent ribs. Each space contains a layer of inspiratory and a layer of expiratory muscle fibers. The inspiratory intercostal muscles form the outer layer, and they slope downward and forward; contraction causes the ribs to move upward and outward, similar to the raising of a bucket handle.

Contraction of these muscles also serves to stabilize the rib cage, making it more rigid, as well as bringing about twisting movements. The stiffening of the rib cage enables it to oppose the tendency to collapse slightly under the influence of the negative pressure generated by the movement of the diaphragm. Without this action, the rib cage would distort, and the action of the diaphragm would be less mechanically efficient, thus wasting energy. Intercostal muscle contraction also brings about stiffening of the rib cage during lifting, pushing, and pulling movements, which makes the intercostal muscles an important contributor to these movements. Some muscles in the neck region also have an inspiratory action. The scalene and sternocleidomastoid muscles (also known as sternomastoid) are attached to the top of the sternum, upper two ribs, and clavicle at one end; at the other end, they are attached to the cervical vertebrae and mastoid process. When these muscles contract, they lift the top of the chest, but the scalene muscles are also involved in flexion of the neck. Expiratory Muscles The principal muscles of expiration are those that form the muscular corset of the abdominal wall.

The most well known and visible of these (at least in male models!) is the rectus abdominis (or “six pack”); the other three muscles are less visible but arguably more functionally important to sports—the transversus abdominis and the internal and external oblique muscles. When these muscles contract, they pull the lower rib margins downward, and they compress the abdominal compartment, raising its internal pressure. The pressure increase tends to push the diaphragm upward into the thoracic cavity, inducing an increase in pressure and expiration. However, these muscles only come into play as breathing muscles during exercise or during forced breathing maneuvers; resting exhalation is a passive process brought about by the recoil of the lungs and rib cage at the end of inspiration (due to stored elastic energy). The four abdominal muscles involved in breathing also have important functions as postural muscles, in rotating and flexing the trunk, and when coughing, speaking (or singing), and playing wind instruments. The compression and stiffening of the abdominal wall generated by contraction of the abdominal muscles also optimize the position of the diaphragm at the onset of inspiration. This also enhances spinal stability and postural control. The rib cage also contains muscles with an expiratory action.

These are the internal intercostal muscles, which slope backward; contraction causes the ribs to move downward and inward, similar to the lowering of a bucket handle. Both internal and external intercostal muscles are also involved in flexing and twisting the trunk. What is the muscular wall that separates the abdominal and thoracic cavities? | Reference.com What is the muscular wall that separates the abdominal and thoracic cavities? A: Quick Answer The diaphragm is the muscular wall that separates the thorax from the abdomen regions. The diaphragm, which is dome-shaped and extends across the rib cage's bottom, is made up of the peripheral muscle and central tendon. Full Answer The diaphragm also has openings that allow for the passage of anatomical structures like the esophagus, descending aorta, vagus nerve and the inferior vena cava. A main function of the diaphragm is to aid respiration. When the diaphragm contracts, it causes an expansion of the lungs as air is breathed in. A diaphragm impairment can cause breathing problems, as stated by MedicineNet. The thoracic cavity contains the esophagus, heart, bronchi and lungs.

The abdominal cavity consists of organs that include the stomach, liver, spleen and pancreas. Thoracic Muscles Thoracic Muscles Science Main Index The main thoracic muscles consist of the intercostal muscles, diaphragm and transversus thoracis. Read on to learn more about the thoracic muscles, and its role in breathing. On this page: Top of Page Thoracic Muscle The intercostal muscles connect between the ribs. They are arranged in three layers: the external layer, the internal layer and the innermost layer. Their primary role is to compress the ribs to exhale air while breathing. The diaphragm extends across the bottom of the rib cage. It separates the thoracic cavity, containing the heart, lungs and ribs, from the abdominal cavity. The diaphragm plays an important role in breathing. The diaphragm and the internal intercostal muscles expand the thoracic cavity to cause inspiration or inhaling of air. The transversus thoracis is on the inner front wall of the rib cage. These muscles also play a role in breathing by compressing the rib cage for exhaling. Unit IV Introduction: We have explored the vertebral column and its muscle attachments and movements.

Now we will consider the thorax and the thoracic cage areas and its relationship to the trunk and extremities. Other important aspects of the thorax are the anatomical structures for respiration (breathing). Breathing is a key element to understand, and must be utilized experientially for the dancer in all movements. Overview of the Thorax The thorax is the superior part of the trunk between the neck and the abdomen. It is formed by the 12 pairs of ribs, the sternum (breast bone), costal cartilages, and the 12 thoracic vertebrae. These bony and cartilagenous structures form the thoracic cage (rib cage) which surrounds the thoracic cavity and supports the shoulder girdle. The thoracic cavity contains the heart, the lungs, and some abdominal organs. The thoracic cage provides attachments for muscles of the neck, thorax, upper limbs, abdomen, and back. The thorax moves up and down to allow breathing, so it is one of the most dynamic regions of the body. The picture below shows the basic structures that form the thorax.

The thoracic vertebrae and their intervertebral discs The ribs and costal cartilages Letï¿½s explore each of these in some detail now. The Sternum The sternum, or breast bone, is the flat, elongated bone that forms the midline of the anterior thoracic cage. It has 3 parts: the manubrium , the body, and the xiphoid process. The Xiphoid Process ï¿½ This is the most inferior component of the sternum. It is a small cartilagenous structure that varies in shape from pointed to blunt. It ossifies by age 40. The Manubrium ï¿½ is like the handle of the sword with the body of the sternum its blade. It is the superior most component of the sternum and has several important indentations. Indentations ï¿½ Jugular notch is the most superior aspect of the manubrium that you can feel at the base of your throat Clavicular notches ï¿½ these are the left and right notches that articulate with the sternal end of the clavical (collar bone). These two bones form an articulation called the sternoclavicular joint.

There is a right and a left sternoclavicular joint. Costal notches ï¿½ these are small notches at the lower end of the manubrium that are attachments for the first ribs on the right and on the left. The Body - This is the longer, narrower portion of the sternum that extends down the front of the chest wall. The body is sometimes called the breast bone and is the hard structure you can feel in the middle of your chest. It houses the costal notches for articulations with ribs 2-7. The Thoracic Vertebrae The 12 thoracic vertebrae have the same bony components as the lumbar vertebrae discussed in Unit III. They also have several additional special features: Costal facets (flat spots for attachments) on the body of the vertebrae for articulation with the ribs. Costal facets on the transverse processes for articulation with the tubercles of the ribs Long spinous processes The attachment location of the rib to the vertebrae is called the costovertebral articulation. (The word costal refers to rib---therefore this is a "rib-vertebrae connection").

This articulation is made up of the head of one rib and the costal facets on the vertebrae of that rib and the vertebrae above. For example: thoracic rib #7 articulates with the costal facets of the lower part of the vertebrae T6 and the upper part of the vertebrae of T7. (See illustration to left) Looking through the rib cage to view the anterior thoracic spine with the corresponding rib attachments. ï¿½ The costotransverse joint articulation is the attachment of the rib (example ï¿½ T7 rib) with the facet on the transverse process of vertebrae T7. **This articulation structure will be important when we explore the movement of the ribs in the next section of this unit. The Ribs The ribs are elongated, flattened, and twisted bones. They are very lightweight and resilient. There are 3 types of ribs: True Ribs ï¿½ ribs 1-7 ; these are attached directly to the sternum through their own costal cartilages.

False Ribs ï¿½ ribs 8-10; their costal cartilages are joined to the rib just above them so their attachment to the sternum is indirect Floating Ribs ï¿½ ribs 11-12; these ribs attach to vertebrae, but not to the sternum so they float on one end Illustration of true, false, and floating ribs in the rib cage Structure of Typical Ribs ï¿½ Ribs 3-10 A typical rib is twisted along its axis and has a sharp bend in the shaft called the costal angle. There are two main parts to the typical rib: the posterior portion and the body Posterior portion ï¿½ This portion of the rib has a head and 2 facets for articulation with the bodies of the thoracic vertebrae. The neck of the rib is located just behind these facets and is a constricted section of the bone. The tubercle is a bony prominence for articulation with the transverse process of the thoracic vertebrae and for attachment of ligaments.

The Body ï¿½ This is the long, curved shaft of the bone; its anterior end attaches to the costal cartilage that then attaches to the sternum. Structure of Atypical Ribs ï¿½ Ribs 1-2, and 11-12 Several ribs have a slightly different structure than the typical ribs, due to their location in the thoracic cage. Ribs 1 and 2 are shorter, flatter, and tilted more forward than the others. Many important nerve trunks and blood vessels pass across rib 1 on the way to the arm. Ribs 11 and 12 are short, floating ribs that do not attach anteriorly to the sternum, so they have no neck or tubercles. Respiration ï¿½ Rib Movement and Thoracic Cage Function for Breathing The attachment of the ribs to the sternum and spine between T1 and T7 (true ribs) limits mobility of the thoracic spine in this area. There is a little mobility where the rib attaches to the cartilage before it attaches to the sternum.

Ribs 8-10 (false ribs) have longer costal cartilages which attach to other cartilage, so this area of the rib cage has more mobility. Ribs 11-12 (floating ribs) have no anterior attachment at all so the greatest mobility of the thoracic spine is in this area. Due to these attachments, the upper ribs move differently from the lower ribs. As you breathe air in (inspiration) *see light pink * the thorax widens as the ribs elevate (move upward). The middle portion of the lower ribs moves more laterally when they elevate. Thoracic Wall Movement ï¿½ This motion of the thoracic wall resembles the movement of a bucket handle. The bucket handle is attached to the bucket on each end and as it lifts it moves laterally and up, but in unison left to right. This increases the lateral excursion or movement of the rib cage. When the upper ribs are elevated the anterior-posterior diameter of the thorax increases. This movement resembles that of a pump handle being pumped up and down. The combination of these movements allows the rib cage to increase in the anterior-posterior and the transverse diameters.

During expiration (breathing out) the ribs move down and medially. The Process of Respiration The diaphragm is the primary muscle for respiration. It is located within the lower aspect of the rib cage. Specifically, it has 3 origin areas - the xiphoid process of the sternum, the inner surfaces of the lower 6 ribs, and a ligamentous structure called the arcuate ligaments that run from the bodies of the upper lumbar vertebrae up to T12. The diaphragm then inserts into a thin, strong tendon called the central tendon or crura which spans the central portion of the muscle and is more anterior. This muscle forms a dome shape in the rib cage and spans the space across the rib cage in a figure eight type of shape. This muscle separates the thoracic and abdominal cavities. Inspiration (Breathing in) - with inspiration the diaphragm descends in the thoracic wall and presses against the abdominal organs below. This results in the thoracic cavity gaining in vertical diameter. There is also movement more laterally as the bucket handle movement of the ribs allows the expansion of the lungs outward. This is an active movement that must overcome resistance for adequate intake of air.

Expiration ï¿½ (Breathing out) ï¿½ with expiration the diaphragm ascends back up to its resting position and the vertical space in the thoracic cavity decreases while the lateral movement pulls down and in. Expiration occurs mostly from elastic recoil of the lungs when the inspiratory muscles relax, so it is a much more passive process. There can be increased expiratory work when there is increased exercise demand on the lungs or with singing. The Muscles of Respiration Inspiration - The diaphragm is the primary muscle used for inspiration, but the internal and external intercostal muscles also play an important role in inspiration. The intercostal muscles are the small muscles that lie in diagonal patterns between the ribs. Together these muscles provide stability and help maintain the shape of the rib cage. The external intercostals are located more externally on the rib cage and pass from the inferior border of the ribs to the superior border of the ribs below. The internal intercostals are on the inner surface of the ribs and insert on the adjacent ribs below them. Lateral view of the internal intercostals. ï¿½ Expiration The primary muscles of expiration are the abdominal muscles, which were discussed in Unit III.

The abdominals - the transversus abdominis, the external and internal obliques can function to raise intra-abdominal pressure to meet the increased demands of breathing as when exercising or dancing and provide forced expulsion of air from the lungs. When this is needed the abdominals fire more actively to produce this motion. In resting breathing, the abdominals provide anterior holding support for the abdominal cavity. The overall movement of the rib cage and trunk is impacted by the respiratory process. Upon inspiration the trunk and rib cage expand and open up so that the movement is more into relative extension of the trunk or opening of the anterior aspect of the body. Similarly, expiration brings the trunk into relative flexion or forward bent posture. Relevance to Dance The dancer can use the action of respiration or ï¿½breathï¿½ to assist in movement intention. If a dancer wants to move toward the ground or an inward contracted posture, active exhalation will use the abdominals to assist in hollowing the abdominal cavity to bring the dancer into a more flexed posture. Conversely, the dancer can use inspiration to open up the chest and lift the arms for a more extended posture. Take a minute and try this now.

Experiment with inhalation and exhalation as you move from more flexed trunk positions to more open and extended trunk positions. How does breathing facilitate or hinder this motion? Accessory Muscles of Respiration The accessory muscles of respiration are muscles in the trunk and lower neck that can be called into action to assist with breathing. These muscles usually have other primary functions and only assist with respiration under certain circumstances ï¿½ usually when more deep or rapid breathing is needed. The accessory muscles include the scalenes and the sternocleidomastoid muscles in the neck, the serratus anterior, and the pectoral muscles in the upper trunk, the upper trapezius and latissimus dorsi muscles of the trunk, and the erector spinae muscles of the back. There are also some smaller, deeper muscles which lie against the rib cage which can also be recruited to assist with respiration. Some of the trunk muscles were discussed in Unit III. The neck muscles will be discussed in more detail in Unit X . When one thinks about breathing it is usually thought of as an upper body activity since the mouth and lungs take in the air.

However, after considering the important role of the diaphragm and the abdominals in respiration it is clear that there is a key central core component for respiration. The diaphragm connects down into the lumbar spine via the crura muscle. It also interdigitates with the abdominal muscles and the iliopsoas muscle (psoas major) to form the abdominal wall. These muscles make an important connection to the lower body. We have not discussed the iliopsoas muscle, but it is an important part of the upper-lower connectivity concept for the body. The Iliopsoas and Its Role in Connectivity The iliopsoas is composed of two muscles ï¿½ the psoas major and the iliacus. The psoas major originates on the transverse process of all lumbar vertebra and the sides of the discs in this area also. It inserts on the lesser trochanter of the femur. The iliacus component of the muscle originates in the iliac fossa of the pelvis and inserts on the lateral aspect of the psoas major at the lesser trochanter.

We will discuss this muscle in more depth when we consider the pelvis region, and again when we explore the hip. The iliopsoas is a powerful hip flexor of the femur and an important part of the pelvic floor, as well as a major element in postural alignment. Its central location in relation to the diaphragm cannot be ignored. It is important to remember that the iliopsoas, in combination with the the quadratus lumborum, and the diaphragm form a kinetic chain to integrate upper and lower body activity through the use of breath. Later in the course, in Units XI and XII, we will consider how this upper-lower connectivity is important for body movement and limb-torso connections, weight shifts, and other movement phrases. This ends the course material for Unit IV. Return to Blackboard to proceed to Unit V. Normal Breathing and the Respiratory Tract RESPIRATORY MANAGEMENT IN SPINAL CORD INJURY: NORMAL BREATHING AND THE RESPIRATORY TRACT NORMAL BREATHING AND THE RESPIRATORY SYSTEM The purpose of the respiratory system is to supply oxygen to body tissues and to remove carbon dioxide, which is a waste product, from the body tissues.

Breathing is the process by which oxygen in the air is brought into the lungs and into close contact with the blood, which absorbs it and carries it to all parts of the body. At the same time, the blood gives up carbon dioxide, which is carried out of the lungs with air breathed out. Upper Respiratory System The parts of the upper respiratory system are illustrated above. The Nasal cavity or Nose is the preferred entrance for outside air to enter into the respiratory system. The Oral cavity or Mouth is an alternative way for air to enter the respiratory system. The Pharynx or Throat collects incoming air from the nose and mouth and passes it downward to the trachea (windpipe). The Epiglottis is a flap of tissue that guards the entrance to the trachea, closing when anything is swallowed in order to prevent food or fluid from entering the lungs. The Larynx or Voice Box contains two vocal cords. Air moving through the larynx creates voice sounds. The Esophagus is the passage leading from the mouth and throat to the stomach. The Trachea or Windpipe is the passage leading from the pharynx to the lungs.

The Bronchi or Tubes are the two main tubes into the lung that divide from the trachea. The bronchi subdivide into the lobar bronchi -- three on the right side and two on the left. These, in turn, subdivide further. Lower Respiratory System The parts of the lower respiratory system are illustrated above. The Bronchioles are the smallest subdivisions of the bronchi, at the end of which are the alveoli (plural of alveolus). The Alveoli are the very small air sacs that are the destination of inhaled air. The capillaries are blood vessels that are imbedded in the walls of the alveoli. The blood discharges carbon dioxide into the alveoli and takes up oxygen from the air in the alveoli. The Lungs are elastic organs with sponge-like tissue. Inhalation requires an active effort, whereas exhalation occurs automatically. The right lung is divided into three lobes and the left is divided into two lobes. The Pleura are the two membranes (actually one continuous membrane folded on itself) that surround each lobe of the lungs and separate the lungs from the chest wall. The pleural space is the space between the two pleura.

Diaphragm is the strong wall of muscle that separates the chest cavity from the abdominal cavity. By moving downwards, it creates suction to draw in air and expand the lungs. Ribs are bones separating and protecting the chest cavity. They move to a limited degree, helping the lungs to expand and contract. Nerve and Muscles of the Respiratory System When a spinal cord injury occurs, the lungs and the alveoli remain the same. However, just as the injury affects the nerves that control the muscles of the arms and legs, it also affects the nerves that activate the muscles used for breathing. There are four sets of muscles that control the respiratory system. The Diaphragm Respiratory system Respiratory system Bronchi: The two main air passages into the lungs. Diaphragm: The main muscle used for breathing; separates the chest cavity from the abdominal cavity. Epiglottis: A flap of cartilage that prevents food from entering the trachea (or windpipe). Esophagus: The tube through which food passes from the mouth down into the stomach. Heart: The muscular organ that pumps blood throughout the body.

Intercostal muscles: Thin sheets of muscle between each rib that expand (when air is inhaled) and contract (when air is exhaled). Larynx: Voice box. Lungs: The two organs that extract oxygen from inhaled air and expel carbon dioxide in exhaled air. Muscles attached to the diaphragm: These muscles help move the diaphragm up and down for breathing. Nasal cavity: Interior area of the nose; lined with a sticky mucous membrane and contains tiny, surface hairs called cilia. Nose hairs: Located at the entrance of the nose, these hairs trap large particles that are inhaled. Paranasal sinuses: Air spaces within the skull. Pharynx: The throat. Pleural membrane: Covering the lung and lining the chest cavity, this membrane has 2 thin layers. Pulmonary vessels: Pulmonary arteries carry deoxygenated blood from the heart and lungs; pulmonary veins carry oxygenated blood back to the heart. Respiratory center: Area of the brain that controls breathing. Ribs: Bones attached to the spine and central portion of the breastbone, which support the chest wall and protect the heart, lungs, and other organs in the chest.

Trachea: Tube through which air passes from the nose to the lungs (also known as the windpipe). Illustration provided by: Leslie Laurien, MSMI ◄ ► Respiratory diaphragm - definition of respiratory diaphragm by The Free Dictionary Respiratory diaphragm - definition of respiratory diaphragm by The Free Dictionary (dī′ə-frăm′) n. 1. Anatomy A muscular membranous partition separating the abdominal and thoracic cavities and functioning in respiration. Also called midriff. 2. A membranous part that divides or separates. 3. A thin disk, especially in a microphone or telephone receiver, that vibrates in response to sound waves to produce electric signals, or that vibrates in response to electric signals to produce sound waves. 4. A contraceptive device consisting of a thin flexible disk, usually made of rubber, that is designed to cover the uterine cervix to prevent the entry of sperm during sexual intercourse. 5. A disk having a fixed or variable opening used to restrict the amount of light traversing a lens or optical system.

[Middle English diafragma, from Late Latin diaphragma, midriff, from Greek, partition, from diaphrassein, to barricade : dia-, intensive pref.; see dia- + phrassein, phrag-, to enclose.] di′a·phrag·mat′ic (-frăg-măt′ĭk) adj. di′a·phrag·mat′i·cal·ly adv. diaphragm (ˈdaɪəˌfræm) n 1. (Anatomy) anatomy any separating membrane, esp the dome-shaped muscular partition that separates the abdominal and thoracic cavities in mammals. 2. (Gynaecology & Obstetrics) a circular rubber or plastic contraceptive membrane placed over the mouth of the uterine cervix before copulation to prevent entrance of sperm 3. any thin dividing membrane 4. (Photography) Also called: stop a disc with a fixed or adjustable aperture to control the amount of light or other radiation entering an optical instrument, such as a camera 5. (Telecommunications) a thin disc that vibrates when receiving or producing sound waves, used to convert sound signals to electrical signals or vice versa in telephones, etc 6.

(Chemistry) chem a. a porous plate or cylinder dividing an electrolytic cell, used to permit the passage of ions and prevent the mixing of products formed at the electrodes b. a semipermeable membrane used to separate two solutions in osmosis 7. (Botany) botany a transverse plate of cells that occurs in the stems of certain aquatic plants [C17: from Late Latin diaphragma, from Greek, from dia- + phragma fence] diaphragmatic adj (ˈdaɪ əˌfræm) n. 1. a wall of muscle and connective tissue separating two cavities, esp. the partition separating the thoracic cavity from the abdominal cavity in mammals. 2. a. a porous plate separating two liquids. b. a semipermeable membrane. 3. a thin disk that vibrates when receiving or producing sound waves, as in a telephone or microphone. 4. a thin, dome-shaped device usu. of rubber for wearing over the uterine cervix during sexual intercourse to prevent conception. 5.

a plate with a hole in the center or a ring that is placed on the axis of an optical instrument, as a camera, and that controls the amount of light entering the instrument. v.t. 6. to furnish with a diaphragm. [1350–1400; < Late Latin diaphragma < Greek diáphragma the diaphragm, midriff =dia- dia - + phrágma a fence] di`a•phrag•mat′ic (-frægˈmæt ɪk) adj. di`a•phrag•mat′i•cal•ly, adv. di·a·phragm (dī′ə-frăm′) 1. A muscle that separates the chest cavity from the abdominal cavity. As the diaphragm contracts and expands, it forces air into and out of the lungs. 2. A thin, flexible disk, especially in a microphone or telephone receiver, that vibrates in response to sound waves to produce electrical signals, or that vibrates in response to electrical signals to produce sound waves. diaphragm The physical element of an optical system which regulates the quantity of light traversing the system.

The quantity of light determines the brightness of the image without affecting the size of the image. diaphragm A muscular sheet used in breathing. It separates the thorax and abdomen. ThesaurusAntonymsRelated WordsSynonymsLegend: Thoracic cavity | definition of thoracic cavity by Medical dictionary Thoracic cavity | definition of thoracic cavity by Medical dictionary Related to thoracic cavity: mediastinum , abdominal cavity , Abdominopelvic cavity cavity [kav´ĭ-te] 1. a hollow or space, or a potential space, within the body or one of its organs; called also caverna and cavum . 2. the lesion produced by dental caries . Cavities in the body. From Applegate, 2000. abdominal cavity the cavity of the body between the diaphragm above and the pelvis below, containing the abdominal organs. absorption c's cavities in developing compact bone due to osteoclastic erosion, usually occurring in the areas laid down first. amniotic cavity the closed sac between the embryo and the amnion, containing the amniotic fluid. cranial cavity the space enclosed by the bones of the cranium.

glenoid cavity a depression in the lateral angle of the scapula for articulation with the humerus. marrow cavity (medullary cavity) the cavity that contains bone marrow in the diaphysis of a long bone; called also medullary canal . nasal cavity the proximal portion of the passages of the respiratory system, extending from the nares to the pharynx; it is divided into left and right halves by the nasal septum and is separated from the oral cavity by the hard palate. oral cavity the cavity of the mouth, bounded by the jaw bones and associated structures (muscles and mucosa). pelvic cavity the space within the walls of the pelvis. pericardial cavity the potential space between the epicardium and the parietal layer of the serous pericardium. peritoneal cavity the potential space between the parietal and the visceral peritoneum. pleural cavity the potential space between the two layers of pleura . pulp cavity the pulp-filled central chamber in the crown of a tooth. cavity of septum pellucidum the median cleft between the two laminae of the septum pellucidum.

Called also pseudocele , pseudocoele , and fifth ventricle . serous cavity a coelomic cavity, like that enclosed by the pericardium, peritoneum, or pleura, not communicating with the outside of the body and lined with a serous membrane, i.e., one which secretes a serous fluid. tension cavity cavities of the lung in which the air pressure is greater than that of the atmosphere. thoracic cavity the portion of the ventral body cavity situated between the neck and the diaphragm; it contains the pleural cavity. tympanic cavity the major portion of the middle ear, consisting of a narrow air-filled cavity in the temporal bone that contains the auditory ossicles and communicates with the mastoid air cells and the mastoid antrum by means of the aditus and the nasopharynx by means of the auditory tube. The middle ear and the tympanic cavity were formerly regarded as being synonymous. uterine cavity the flattened space within the uterus communicating proximally on either side with the fallopian tubes and below with the vagina.

tho·rac·ic cav·i·ty [TA] the space within the thoracic walls, bounded below by the diaphragm and above by the base of the neck or superior thoracic aperture. thoracic cavity Etymology: Gk, thorax, chest; L, cavum the cavity enclosed by the ribs, the thoracic part of the vertebral column, the sternum, the diaphragm, and associated muscles. Thoracic cavity tho·rac·ic cav·i·ty (thōr-as'ik kav'i-tē) [TA] The space within the thoracic walls, bounded below by the diaphragm and above by the neck. THORACIC CAVITY thoracic cavity The part of the ventral cavity above the diaphragm, the domed muscle that separates it from the abdominal cavity; it is enclosed by the chest wall.

The thoracic viscera include the pleural membranes that surround the lungs, the mediastinum between the lungs, which contains the heart and pericardial membranes, the thoracic aorta, pulmonary artery and veins, vena cavae, thymus gland, lymph nodes, trachea, bronchi, esophagus, and thoracic duct. See: illustration the space within the THORAX . cavity 1. a hollow or space, or a potentional space, within the body (e.g. abdominal cavity) or one of its organs (e.g. cranial cavity). 2. in teeth, the lesion produced by dental caries . absorption c's cavities in developing compact bone due to osteoclastic erosion, usually occurring in the areas laid down first. amniotic cavity the closed sac between the embryo and the amnion, containing the amniotic fluid. cranial cavity the space enclosed by the bones of the cranium. dental cavity 1. the central space, often branched or multiple in compound teeth, of each tooth; carries the nerve and blood supplies to the teeth. 2. the defect caused by decay on a tooth surface. Called also caries .

glenoid cavity a depression in the ventral angle of the scapula for articulation with the humerus. infraglottic cavity the space in the larynx caudal to the vocal folds; reflects the shape of the cricoid cartilage. medullary (marrow) cavity the cavity, containing marrow, in the diaphysis of a long bone; called also medullary canal. nasal cavity the proximal part of the respiratory tract, within the nose, bisected by the nasal septum and extending from the nares to the pharynx. Much of the cavity is occupied by the turbinate bones or conchae which also divide it into dorsal, medial and ventral meatuses. The common meatus is the narrow, vertical passage close to the nasal septum. The rostral end of the cavity just inside the nostril is the nasal vestibule, and the caudal part opening into the pharynx is the nasopharyngeal meatus. oral cavity the cavity of the mouth, made up of a vestibule and oral cavity proper. pelvic cavity the space within the walls of the pelvis.

pericardial cavity the potential space between the epicardium and the parietal layer of the serous pericardium. peritoneal cavity the potential space between the parietal and the visceral peritoneum. pleural cavity the potential space between the parietal and the visceral pleura. pulp cavity the pulp-filled central chamber in a tooth; called also dental cavity. serous cavity a celomic cavity, like that enclosed by the pericardium, peritoneum or pleura, not communicating with the outside of the body and lined with a serous membrane, i.e. one which secretes a serous fluid. tension cavity cavities of the lung in which the air pressure is greater than that of the atmosphere. thoracic cavity the body cavity situated between the neck and the diaphragm. tympanic cavity the cavity of the middle ear. uterine cavity the space within the uterus communicating on either side with the uterine tubes and caudally with the vagina. thoracic pertaining to the chest. See also thoracolumbar . thoracic asymmetry if obviously distorted can mean that the flatter side has a collapsed lung.

Not a helpful sign in cattle because of the normal asymmetry caused by the rumen. thoracic breath sounds breath sounds produced in the bronchi, bronchioles and alveoli by the passage of air; contrast with tracheal breath sounds. thoracic cage the bony structure enclosing the thorax, consisting of the ribs, vertebral column and sternum. thoracic cavity see thorax ; called also chest. thoracic duct ligation a surgical procedure used in the treatment of chylothorax where medical management is unsuccessful. thoracic girdle the incomplete ring of bones that support the thoracic limb, made up of the scapula, clavicle, coracoid and occasionally other elements. Mammals have no coracoids (except in monotremes) and nongrasping animals have no clavicle so that the girdle consists only of the scapula. Grasping or climbing animals have a clavicle. Birds have a complete bony girdle. Called also pectoral girdle. thoracic inlet the entrance of the chest between the two first ribs, the manubrium, and the first thoracic vertebra.

thoracic limb forelimb. thoracic pain such as that caused by broken ribs, torn intercostal muscles, pleurisy can cause a grunt at the end of each inspiration. thoracic peristaltic sounds can be of assistance in diagnosing diaphragmatic hernia in a dog or cat but they occur commonly in normal horses and cattle. thoracic positioner a sterilizable M-shaped metal trough which can be laid on an operating table and an animal propped up in it for surgery. thoracic respiration the diaphragm and abdominal muscles remain immobilized and play little part in respiration, as in peritonitis with diaphragmatic hernia. thoracic segmental spinal cord degeneration characteristic lesion in the inherited disease merino degenerative axonopathy . thoracic surgery surgical procedures involving entrance into the chest cavity. Until techniques for endotracheal anesthesia were perfected, this type of surgery was extremely dangerous because of the possibility of lung collapse. By administering anesthesia under pressure through an endotracheal tube it is now possible to keep one or both lungs expanded, even when they are subjected to atmospheric pressure.

thoracic symmetry lack of symmetry between the two sides, viewed from above, can suggest lung collapse or a space-occupying lesion on the smaller side; in ruminants the presence of the rumen always enhances the size of the left side. thoracic tube see chest tube . thoracic vertebrae the vertebrae between the cervical and lumbar vertebrae, giving attachment to the ribs and forming part of the dorsal wall of the thorax. thoracic wall includes the ribs, sternum and thoracic vertebrae, the intercostal, superficial and deep, muscles, and the external respiratory muscles (transverse thoracic, rectus thoracic, serratus dorsalis and scalenus), and the costal pleura. thoracic wall flap a surgical approach to the thoracic cavity that combines an intercostal incision and sternotomy. It allows great exposure to structures of the cranial mediastinum and caudal cervical region. thoracic wall wound penetration through to the pleural cavity results in pneumothorax and collapse of the lung on that side.

Diaphragm is a large skeletal muscle that separates the - BIO - 160 View Full Document Diaphragm- is a large skeletal muscle that separates the thoracic cavity from the abdominal cavity. It is the main structure in respiration. Bronchiole- the bronchi branches off into smaller tubes that end up in the pulmonary alveolus Pharynx- Is a tube at the back of the nasal cavity and the mouth. It contains a passageway for both food and air. Epiglottis- is a flap of elastic cartilage that acts as switch between the trachea and the esophagus This preview has intentionally blurred sections. Sign up to view the full version. View Full Document Larynx- is also called the voice box, is a short section of the airway that produces sounds when air is forced past the vocal cords. Rib muscles - the muscles between the ribs in the chest 2. Explain the function of the ribs and diaphragm in the breathing process. Breathing is the process of moving air in and out of the lungs. When you inhale , your chest expands as muscles contract to move the ribs up and out.

At the same time, your diaphragm flattens and pushes down on the abdomen. Muscles in the abdomen wall then relax, proving room for the flattened diaphragm. When the diaphragm flattens and the ribs are lifted up and out, the volume of the lungs increases. The increased volume reduces the air pressure in the lungs. By this point, the pressure in the lungs is lower than the pressure outside so the air then moves inside the lungs. When you exhale , the reverse movements take place. The diaphragm and rib muscles relax and the elastic tissues in the lungs recoil and deflate the lungs. The volume decreases and the air pressure inside the cavity become greater than the outside. This pressure forces the air out. 3. Explain how breathing rate is controlled The rate of breathing is controlled by the brain and brain stem, which monitor the amount of carbon dioxide in the blood. When activity increase the level of carbon dioxide in the blood is high and it stimulate nerve cells in the brain. Then the brain stem stimulates the diaphragm to increase the breathing rate and depth. The same process occurs when the carbon concentration is lower and stimulates slower breathing. A person can override the respiratory control center by holding their breath. 4.

Describe what happens between the alveoli and the capillaries. Gas exchange between the alveoli and the blood capillaries occur in the lungs. Oxygen that is being transported moves through the blood stream and carbon dioxide that is to eliminated from body goes to the alveoli. When air moves in the lungs, the oxygen crosses the alveolar membranes and the capillary walls and dissolves in the blood. Carbon moves in the opposite direction crossing the capillary walls first then the alveolar membranes entering the alveoli. Air that moves into the alveoli This is the end of the preview. Sign up to access the rest of the document. TERM Photosynthesis Energy Transformations ATP is the energy molecule used in all living photosynthesis_powerpoint

Question: What is the name of the chief muscle used in breathing, which separates the thoracic cavity from the abdominal cavity?
Answer: Diaphragm